Build an ADU in Danbury.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Danbury — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
2 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Danbury zoning ordinance · source · 2026-07-07
- Front
- 30 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 87,120 sf (~2.00 ac)
The entire town is one rural district (11.1); one- and two-family dwellings are permitted uses (11.3.1), with only one principal residential structure per lot plus accessory structures and one ADU (11.2.1).
- Front
- 30 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
Overlay on the townwide rural district covering the Danbury Village and South Danbury Village centers (boundaries described in 11.4.6 - generally 500-ft strips either side of NH 104 / US 4 / lower High St in Danbury Village, and a strip along US 4 at the Wilmot line in South…
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Danbury ADU FAQ
Yes. Under NH RSA 674:71-73 (HB 577), one accessory dwelling unit is allowed by-right on single-family lots statewide, including Danbury (Merrimack County). A detached ADU can be up to 950 sf.
In Danbury's RD zone, ADUs follow the single-family setbacks: 30 ft front, 20 ft side, and 20 ft rear. Danbury has 2 zoning districts in total — see the full table below. Confirm your exact zone with the town.